Biotechnology Bulletin

   

Cloning and Functional Characterization of HvNAC53 from Hulless Barley

HE Jing-jing, PENG Mao-la-zhuan, YAO Xiao-hua, YAO You-hua, WU Kun-lun(), CUI Yong-mei()   

  1. Qinghai -Xizang Plateau Germplasm Resource Research and Utilization Laboratory, Qinghai Provincial Key Laboratory of Barley Genetics and Breeding, Qinghai Barley Sub-Center of the National Cereal Improvement Center, College of Agriculture and Forestry, Qinghai University, Xining 810016
  • Received:2026-01-04 Online:2026-06-30
  • Contact: WU Kun-lun, CUI Yong-mei E-mail:wklqaaf@sina.com;15251892177@163.com

Abstract:

Objective NAC (NAM/ATAF1/2/CUC2) transcription factors are a crucial class of regulatory proteins in plants, extensively involved in growth, development, and responses to biotic and abiotic stresses. This study aimed to clone the HvNAC53 gene from hulless barley (Hordeum vulgare var. nudum), analyze its sequence characteristics and expression patterns, and functionally characterize it, thereby providing a theoretical basis for stress-tolerant molecular breeding in hulless barley. Methods The HvNAC53 gene was cloned from the hulless barley cultivar ‘Kunlun 14’. Bioinformatics analysis and RT-qPCR were used to analyze gene expression and protein characteristics. The role of HvNAC53 in response to low-temperature and drought stress was investigated through heterologous overexpression in Arabidopsis thaliana. Results The open reading frame of HvNAC53 is 1 550 bp in length, encoding a protein of 305 amino acids. The protein lacks transmembrane domains and signal peptides and is classified as a hydrophilic, unstable protein. Multiple cis-acting elements responsive to light, hormones, and stress were identified in the promoter region of HvNAC53. Phylogenetic analysis indicated that HvNAC53 is most closely related to TeNAC53 from Thinopyrum elongatum (tall wheatgrass). RT-qPCR results revealed high expression levels of HvNAC53 in roots and leaves compared to other tissues, and its expression was significantly induced by drought and cold stress. Subcellular localization demonstrated that HvNAC53 is localized in the nucleus. Furthermore, Arabidopsis thaliana lines heterologously overexpressing HvNAC53 exhibited significantly higher cold and drought tolerance than wild-type plants. Conclusion HvNAC53 positively regulates low-temperature and drought stress responses in hulless barley.

Key words: hulless barley, HvNAC53, low temperature, drought, heterologous overexpression, subcellular localization